Kindergartners who were given "good bacteria" supplements as infants were no less likely to suffer from allergies than other kids in a new study from Australia. The findings, reported in the Journal of Allergy and Clinical Immunology, add to a mixed bag of results from research into whether probiotics can help ward off kids' allergies. Based on what's known so far, it may be that only certain probiotics are helpful for certain kids - but even then, the benefit seems "very modest," according to Dr. Sonia Michail, a pediatric gastroenterologist at Children's Hospital Los Angeles who was not involved in the work.